The present invention relates to an improved control cable.
The control cable comprises essentially a flexible conduit (in some cases, a non-flexible one) and a flexible inner cable inserted into the conduit, and is used for transmitting a power which is obtained by operating one end of the inner cable by means of pull, push-pull or rotation to the another end thereof. Therefore, the control cable is frequently adopted for the remote control in the various machines or equipments in industry.
Since the conduit is generally formed from a metal spiral tube so as to be capable of enduring the operation of the inner cable as mentioned above, and the inner cable is generally formed from metal strand wires, the conduit and the inner cable are scraped against each other in the above operation, whereby the control cable generates a noise, and further generates frictional resistance. To exclude such a problem, various methods are proposed prior to the present application.
The control cable which has the inner tube formed from a synthetic resin, e.g. nylon resin, between the conduit and the inner cable is, for example, proposed for excluding the above problem. However, such a control cable is not especially sufficient to prevent the noise, since the inner tube is merely formed by molding of the synthetic resin.
In a automobile, a large number of control cables are used for the various remote controls, for example, raising and lowering of a window glass, opening and shutting of a sliding roof, of a trunk lid, functioning of a speedometer, operating of a choke, of a accelerator, of a driving-mirror, or the like. However, the generated noise gives uncomfortableness to a driver and a passenger, even if the noise is slight. In addition, the noise generated from the control cable by the vibration of the automobile also gives uncomfortableness to them. Accordingly, it is required to prevent the noise as much as possible.
Then, in the other conventional control cable proposed, a brush-like hairiness is adhered to either an outer circumference of the inner cable or an inner circumference of the conduit. However, such a control cable has drawbacks wherein; the hairiness tends to take off easily and wears with use of a comparatively short duration, and further the operation of the inner cable is prevented by the accumulation thereto of the hairiness taken off, and as a result, the control cable cannot achieve the original purpose.